When we were shopping last year for a "gently" used unit we ruled out anything with a slide longer than 14 - 20 feet. We looked at a non Thor 38' MH that had a full slide probably over 30' long that held the large frig in it and other heavy items.
Full Time in 2017 Newmar Ventana 4369
pulling a 24' enclosed (Mini Cooper/Harley/Kayak)
(traded 2014 Thor Challenger)
US Army 70-73 Retired LEO